California lightning risk

58 counties scored 1 rated Very High

Los Angeles County has the highest lightning risk in California, scoring 96.9 out of 100 — rated "Very High" by FEMA's National Risk Index. Recorded lightning events across California have decreased 43% over the past five years compared to the prior five-year period.

# County NRI score Rating NOAA events
2016–2026
1 Los Angeles County 96.9 Very High 1
2 San Bernardino County 95.2 Relatively High 16
3 Tulare County 94.9 Relatively High 1
4 San Joaquin County 93.4 Relatively High 0
5 Stanislaus County 91 Relatively High 2
6 Contra Costa County 90.8 Relatively High 0
7 Kern County 85 Relatively High 1
8 Fresno County 84.7 Relatively High 3
9 Merced County 84.6 Relatively High 1
10 Placer County 81.9 Relatively High 1
11 Riverside County 81.5 Relatively Moderate 10
12 San Diego County 80.9 Relatively Moderate 19
13 Plumas County 80.4 Relatively Moderate 0
14 Sierra County 77.6 Relatively Moderate 1
15 Tuolumne County 73.5 Relatively Moderate 0
16 Madera County 72.8 Relatively Moderate 0
17 Nevada County 70.5 Relatively Moderate 0
18 Ventura County 70.2 Relatively Moderate 0
19 Mariposa County 69.2 Relatively Moderate 1
20 El Dorado County 69 Relatively Moderate 0
21 San Mateo County 68.2 Relatively Moderate 4
22 Butte County 68.1 Relatively Moderate 2
23 Orange County 66.9 Relatively Moderate 1
24 Shasta County 66.8 Relatively Moderate 2
25 Monterey County 63.7 Relatively Moderate 3
26 Sacramento County 63.3 Relatively Moderate 0
27 Solano County 60.3 Relatively Moderate 0
28 Santa Cruz County 59.2 Relatively Moderate 0
29 Sonoma County 58.7 Relatively Moderate 2
30 Calaveras County 56.1 Relatively Low 0
31 Santa Barbara County 55.4 Relatively Low 0
32 Amador County 52.8 Relatively Low 0
33 Sutter County 49.6 Relatively Low 0
34 Kings County 48.2 Relatively Low 1
35 Alameda County 47.5 Relatively Low 1
36 Santa Clara County 46.9 Relatively Low 5
37 Yolo County 44.3 Relatively Low 0
38 Yuba County 40 Relatively Low 0
39 Tehama County 39.6 Relatively Low 1
40 Siskiyou County 35.3 Relatively Low 1
41 Marin County 34.1 Relatively Low 1
42 Inyo County 33.9 Relatively Low 1
43 Lassen County 33.8 Relatively Low 0
44 Humboldt County 32.9 Relatively Low 0
45 Napa County 30.2 Relatively Low 1
46 San Francisco County 29.9 Relatively Low 6
47 Mendocino County 29.4 Relatively Low 0
48 Mono County 27.2 Relatively Low 1
49 San Luis Obispo County 25.4 Relatively Low 0
50 Lake County 22.1 Very Low 1
51 Glenn County 19.9 Very Low 0
52 Colusa County 16.2 Very Low 0
53 Imperial County 16 Very Low 0
54 San Benito County 12.5 Very Low 0
55 Del Norte County 12.4 Very Low 0
56 Trinity County 11.3 Very Low 0
57 Modoc County 9.9 Very Low 0
58 Alpine County 3.1 Very Low 0

Source: FEMA National Risk Index v1.20.0, December 2025. Scores are 0–100 percentile rankings among all US counties. See the methodology page for definitions. Download the full CSV for all counties.

Lightning risk nationally:

Other hazard risks in California:

Frequently asked questions

What is the highest lightning risk county in California?

Los Angeles County, CA has the highest lightning risk in California, with a FEMA National Risk Index score of 96.9 out of 100 (rated "Very High").

How many counties in California are rated Very High for lightning risk?

1 of 58 scored California counties are rated "Very High" for lightning risk by FEMA's National Risk Index.

What causes lightning risk in California?

Lightning risk reflects expected annual losses from cloud-to-ground strikes, which ignite building fires, damage electrical systems, and cause fatalities. Florida consistently leads the US in lightning density. High scores also appear across the Gulf Coast, Southeast, and central Plains, where afternoon convective storms are most frequent in summer months.